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Personal homepage of Dr. Jan Wilhelm


Research

Our research is located in the fields between theoretical condensed matter physics, theoretical optics and theoretical chemistry. We employ computer simulations to understand various physical effects as high-harmonic generation in solids and to predict electronic quasiparticle levels of molecules from GW.

High-Harmonic Generation in Solids

Absorption and emission of light in the bandstructure of a solid.

When irradiating solids with a laser pulse of frequency $\omega$, the emitted radiation can feature high-harmonic frequencies $n\omega,n\in\mathbb{N}$. We simulate high-harmonic generation by electron quantum dynamics to explore exciting physics in exotic materials in close collaboration with Prof. Huber's group.

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Low-scaling GW Calculations

'GW meter': Computational cost of GW can be reduced from $O(N^4)$ to $O(N^2)$.

GW is the state-of-the-art method to compute band structures of solids and electronic levels in molecules. Today's largest supercomputers are required, when applying GW to systems with more than ten atoms. We work on a low-scaling GW algorithm to enable GW for thousands of atoms.

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Teaching

SS 2021: Computational Nanoscience (lecture and exercises)
SS 2020: Computational Nanoscience (lecture and exercises)
WS 2019/2020: Integrated Course II: Statistical Physics and Solid State Physics (exercises)


Short CV

12/2019 - present: Akademischer Rat (lecturer position), University of Regensburg
2017 - 2019: Research Scientist, BASF SE, Ludwigshafen
2014 - 2017: Dr. sc. nat. in Theoretical Chemistry, University of Zurich
2012 - 2016: B.Sc. in Mathematics, Karlsruhe Institute of Technology (KIT)
2009 - 2014: B.Sc., M.Sc. in Physics, KIT


Publications

The publication list is also available on Google Scholar.

  1. J. Wilhelm, P. Seewald, D. Golze: Low-scaling GW with benchmark accuracy and application to phosphorene nanosheets, arXiv:2012.06321 (2020).
  2. J. Wilhelm, P. Grössing, J. Crewse, M. Nitsch, L. Weigl, C. Schmid, F. Evers: Semiconductor-Bloch Formalism: Derivation and Application to High-Harmonic Generation from Dirac Fermions, arXiv:2008.03177 (2020).
  3. T. D. Kühne, M. Iannuzzi, M. Del Ben, V. V. Rybkin, P. Seewald, F. Stein, T. Laino, R. Z. Khaliullin, O. Schütt, F. Schiffmann, D. Golze, J. Wilhelm, S. Chulkov, M. H. Bani-Hashemian, V. Weber, U. Borstnik, M. Taillefumier, A. S. Jakobovits, A. Lazzaro, H. Pabst, T. Müller, R. Schade, M. Guidon, S. Andermatt, N. Holmberg, G. K. Schenter, A. Hehn, A. Bussy, F. Belleflamme, G. Tabacchi, A. Glöß, M. Lass, I. Bethune, C. J. Mundy, C. Plessl, M. Watkins, J. VandeVondele, M. Krack, J. Hutter: CP2K: An electronic structure and molecular dynamics software package - Quickstep: Efficient and accurate electronic structure calculations, J. Chem. Phys. 152, 194103 (2020).
  4. T. T. Duignan, G. K. Schenter, J. L. Fulton, T. Huthwelker, M. Balasubramanian, M. Galib, M. D. Baer, J. Wilhelm, J. Hutter, M. Del Ben, X. S. Zhao, C. J. Mundy: Quantifying the hydration structure of sodium and potassium ions: taking additional steps on Jacob’s Ladder, Phys. Chem. Chem. Phys. 22, 10641-10652 (2020).
  5. J. I. Urgel, S. Mishra, H. Hayashi, J. Wilhelm, C. A. Pignedoli, M. Di Giovannantonio, R. Widmer, M. Yamashita, N. Hieda, P. Ruffieux, H. Yamada, R. Fasel: On-surface light-induced generation of higher acenes and elucidation of their open-shell character, Nat. Commun. 10, 861 (2019).
  6. D. Beyer, S. Wang, C. A. Pignedoli, J. Melidonie, B. Yuan, C. Li, J. Wilhelm, P. Ruffieux, R. Berger, K. Müllen, R. Fasel, X. Feng: Graphene Nanoribbons Derived From Zigzag Edge-Encased Poly (para-2, 9-dibenzo [bc, kl] coronenylene) Polymer Chains, J. Am. Chem. Soc. 141, 2843-2846 (2019).
  7. J. Wilhelm, J. VandeVondele, V. V. Rybkin: Dynamics of the Bulk Hydrated Electron from Many‐Body Wave‐Function Theory, Angew. Chem. Int. Ed. 58, 3890-3893 (2019).
  8. D. Golze, J. Wilhelm, M. J. van Setten, P. Rinke: Core-level binding energies from GW: An efficient full-frequency approach within a localized basis, J. Chem. Theory Comput. 14, 4856-4869 (2018).
  9. M. Di Giovannantonio, J. I. Urgel, U. Beser, A. V. Yakutovich, J. Wilhelm, C. A. Pignedoli, P. Ruffieux, A. Narita, K. Müllen, R. Fasel: On-Surface Synthesis of Indenofluorene Polymers by Oxidative Five-Membered Ring Formation, J. Am. Chem. Soc. 140, 3532-3536 (2018).
  10. J. Wilhelm, D. Golze, L. Talirz, J. Hutter, C. A. Pignedoli: Toward GW calculations on thousands of atoms, J. Phys. Chem. Lett. 9, 306-312 (2018).
  11. J. Wilhelm, J. Hutter: Periodic GW calculations in the Gaussian and plane-waves scheme, Phys. Rev. B 95, 235123 (2017).
  12. D. Golze, N. Benedikter, M. Iannuzzi, J. Wilhelm, J. Hutter: Fast evaluation of solid harmonic Gaussian integrals for local resolution-of-the-identity methods and range-separated hybrid functionals, J. Chem. Phys. 146, 034105 (2017).
  13. J. Wilhelm, P. Seewald, M. Del Ben, J. Hutter: Large-scale cubic-scaling random phase approximation correlation energy calculations using a Gaussian basis, J. Chem. Theory Comput. 12, 5851-5859 (2016).
  14. J. Wilhelm, M. Del Ben, J. Hutter: GW in the Gaussian and plane waves scheme with application to linear acenes, J. Chem. Theory Comput. 12, 3623-3635 (2016).
  15. J. Wilhelm, M. Walz, F. Evers: Ab initio spin-flip conductance of hydrogenated graphene nanoribbons: Spin-orbit interaction and scattering with local impurity spins, Phys. Rev. B 92, 014405 (2015).
  16. M. Walz, J. Wilhelm, F. Evers: Current patterns and orbital magnetism in mesoscopic dc transport, Phys. Rev. Lett. 113, 136602 (2014).
  17. J. Wilhelm, M. Walz, F. Evers: Ab initio quantum transport through armchair graphene nanoribbons: Streamlines in the current density, Phys. Rev. B 89, 195406 (2014).
  18. N. Bajales, S. Schmaus, T. Miyamashi, W. Wulfhekel, J. Wilhelm, M. Walz, M. Stendel, A. Bagrets, F. Evers, S. Ulas, B. Kern, A. Böttcher, M. M. Kappes: C58 on Au (111): A scanning tunneling microscopy study, J. Chem. Phys. 138, 104703 (2013).
  19. J. Wilhelm, M. Walz, M. Stendel, A. Bagrets, F. Evers: Ab initio simulations of scanning-tunneling-microscope images with embedding techniques and application to C58-dimers on Au(111), Phys. Chem. Chem. Phys. 15, 6684-6690 (2013).

Book

Stoffumwandlungen und Bilanzen: Ein Lehrbuch für Wirtschaftsingenieure, 2012/2013
(in German; book for industrial engineering students at KIT to prepare for chemical engineering exam; passing the exam was mandatory until 2015 to obtain B.Sc. degree in industrial engineering; ISBN: 978-3000431555)


Contact
Email: jan.wilhelm(at)ur.de
Phone: +49 (0) 941 943 2040
Office: PHY 3.1.24

Address
Institute of Theoretical Physics
Universitätsstraße 31
D-93053 Regensburg

 
Last modified: 23rd Jan, 2021 by Jan Wilhelm